In a recent paper [1]} we discussed this problem, pointing up that these two different populations, i.e. the non-thermal electrons and the high temperature gas, are linked each other because of the effect of the Coulomb interactions. In particular, a higher density of the thermal gas implies a higher rate of the Coulomb losses, which have the effect of reducing the density of the low energy non-thermal electrons and therefore of flattening their spectrum, and as a consequence of reducing the intensity of the non-thermal SZE. Therefore, this effect should be taken into account when interpreting the results of observations of the SZE inside the cluster cavities in terms of thermal or non-thermal populations.
